<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    * {
      padding: 0;
      margin: 0;
    }

    .phone {
      width: 300px;
      height: 500px;
      border: 1px solid #333;
      border-radius: 10px;
      margin: 50px auto;
      position: relative;
    }

    .slideBar {
      width: 100%;
      height: 45px;
      background-color: grey;
      position: absolute;
      top: 70%;
      left: 0;
    }

    .ball {
      width: 45px;
      height: 45px;
      border-radius: 50%;
      background-color: pink;
      position: absolute;
      left: 0;
    }
  </style>
</head>

<body>
  <div class="phone">
    <div class="slideBar">
      <div class="ball"></div>
    </div>
  </div>
</body>
<script>
  var phone = document.getElementsByClassName("phone")[0];
  var slideBar = document.getElementsByClassName("slideBar")[0];
  var ball = document.getElementsByClassName("ball")[0];

  var maxLeft = slideBar.clientWidth - ball.clientWidth;
  ball.onmousedown = function (e) {
    var e = e || window.event;
    var posX = e.offsetX;

    document.onmousemove = function (e) {
      var e = e || window.event;
      var x = e.pageX - posX - phone.offsetLeft;

      if (x < 0) x = 0;
      if (x > maxLeft) x = maxLeft;

      ball.style.left = x + "px";

      if (x == maxLeft) {
        location.href = "https://www.baidu.com";
      }

    }
    document.onmouseup = function () {
      document.onmousemove = null;
      if (ball.offsetLeft == maxLeft) {
        location.href = "https://www.baidu.com";
      } else {
        ball.style.left = 0 + "px";
      }
    }
  }



</script>

</html>